The Eco-ball, an experimentally designed closed ecosystem, features water plants that produce food and oxygen; fish, shrimps and shellfish that consume oxygen and food and generate carbon dioxide and organic substances (e.g. excrement); and microorganisms that decompose the excrement, waste and other organic substances. These organisms live in complex relationships with each other. The electric bulb installed on the Eco-ball provides the light necessary for photosynthesis by the water plants. It also heats the Eco-ball. The temperature of the Eco-ball is sometimes influenced by room temperature.
The exhibit is modeled after the Earth.